Heel downholder for safety ski bindings

ABSTRACT

A base member is adapted to be fixed with respect to the top surface of a ski. A pivoting member is mounted on the base member about a first transverse pivot pin. A jaw adapted to grip the heel of the ski boot is carried by the pivoting member. A cam following pin is carried by the pivoting member. A third transverse pivot pin is rotatably mounted on the base member. A pivoting lever is rigid with the third transverse pivot pin. A cam member for controlling the movement of the cam following pin from a first to a second position with respect to the cam member is carried by the pivoting lever. The downholder is at a lowermost position when the cam following pin is at its first position. The pivoting lever is adapted to constitute a release lever for controlling the retraction of the cam member. The third rotary transverse pivot pin has a planar abutment surface including a pair of edges parallel to each other and to the axis of the third pivot pin. A piston having a complementary planar surface is adapted to contact the abutment surface. The plane containing the abutment surface is perpendicular to the axis of the piston when the downholder is in its lowermost position. A compression spring urges the piston against said edges.

United States Patent [72] Inventor Jean Joseph Alfred Hey] 1, rue Devieur Robelin, Nevers, France [21] Appl. No. 808,112 [22] Filed Mar. 18, 1969 [45] Patented May 25, 1971 [32] Priority Mar. 22, 1968 [3 3 France [31 144,577

[54] HEEL DOWNHOLDER FOR SAFETY SK! BINDINGS 7 Claims, 7 Drawing Figs.

[52] US. Cl 280/11.35T l 1 A63c 9/00 [50] Field ofSearch 280/11.35

[56] References Cited UNITED STATES PATENTS 3,317,217 5/1967 Poiger 280/1 1.35 3,447,812 6/1969 Koji Kato 280/11.35

Primary ExaminerBenjamin Hersh Assistant ExaminerRobert R. Song Attorneys-Harry C. Bierman, Jordan B. Bierman and Bierman and Bierman ABSTRACT: A base member is adapted to be fixed with respect to the top surface of a ski. A pivoting member is mounted on the base member about a first transverse pivot pin. A jaw adapted to grip the heel of the ski boot is carried by the pivoting member. A cam following pin is carried by the pivoting member. A third transverse pivot pin is rotatably mounted on the base member. A pivoting lever is rigid with the third transverse pivot pin. A cam member for controlling the movement of the cam following pin from a first to a second position with respect to the cam member is carried by the pivoting lever. The downholder is at a lowermost position when the cam following pin is at its first position. The pivoting lever is adapted to constitute a release lever for controlling the retraction of the cam member. The third rotary transverse pivot pin has a planar abutment surface including a pair of edges parallel to each other and to the axis of the third pivot pin. A piston having a complementary planar surface is adapted to contact the abutment surface. The plane containing the abutment surface is perpendicular to the axis of the piston when the downholder is in its lowermost position. A compression spring urges the piston against said edges.

PATENTED HAYZS I971 SHEET 3 [IF 3 HEEL DOWNHOLDER FOR SAFETY SKI BINDINGS The present invention relates to safety heel downholding devices of the type designed for maintaining the heel portion of a ski boot on a ski and automatically releasing the boot in case of forward fall of the skier.

More particularly, this invention relates to heel downholders of the type wherein the heel gripping jaw is carried by a support pivotally mounted about a transverse pin carried in turn by a base member, and the resilient-action retaining mechanism housed in said base member is adapted to act upon a cam following pin carried by said support, this last-named action being exerted through the medium of a cam-forming movable member, a release lever being provided on the other hand for enabling the skier to voluntarily control the retraction of this movable member.

A number of heel downholders of this general type are already known in the art; however, these known structures are generally objectionable on account of the relative complexity of their mechanisms, and also for various inconveniences.

In a known type of heel downholder for ski bindings the cam-forming member controlling the support of the heelgripping jaw is connected to the base member through the mediumof a pair of links, the assembly acting somewhat like a hinged quadrilateral.

Under these conditions, this known device comprises four transverse pivot pins, in addition to the pivot pin of the jawsupporting member and to the pivot pin carried by this lastnamed supporting member, which is responsive to the aforesaid cam-forming member.

In the same construction the release lever consists of an extension carried by one of the connecting links between the cam-forming movable member and the base member.

Besides, due to the very nature of the arrangement thus proposed thespring controlling the resilient retaining mechanism is not protected against the detrimental action of snow and ice. Therefore, the operation of this heel downholder cannot be regarded as fully reliable. Finally, this known construction is also objectionable in that it will release the ski boot immediately when the heel is slightly raised from the normal skiing position. Therefore, this device is most likely to untimely free the ski boot when the latter is slightly raised as in normal skiing conditions, for example when clearing small ground unevennesses.

To avoid this inconvenience, skiers are thus compelled to reinforce the resistance provided by the resilient retaining mechanism, but in this case the heel downholder may fail from releasing the ski boot when necessary.

Besides, experience teaches that obtaining a high degree of safety under normal skiing conditions requires in a ski binding, and notably in the case of a heel downholder, the possibility of a relatively long movement or stroke before the boot is actually freed.

Now, various safety heel downholders have already been proposed which comprise a resilient retaining mechanism permitting a relatively long prerelease stroke or movement. Thus, the U.S. Pat. No. 3,I73,701 in the applicant's name describes and illustrates a heel downholder wherein the retaining mechanism comprises a piston responsive to a compression spring and reacting against a pair of fixed edges formed on the pivot pin.

This mechanism is advantageous in that it permits the upward movement of the heel-gripping jaw when necessary, and then the automatic return of this support to its initial position, without untimely releasing the boot in case the latter were slightly raised off the ski surface under normal skiing conditions. Besides, this mechanism affords a considerable release stroke before actually releasing the boot. However, the corresponding heel downholder is relatively complicated and costly. On the other hand, its overall dimensions are rather considerable.

It is therefore the essential object of the present invention to avoid these various inconveniences. To this end, a first object of the present invention consists in providing a heel downholder of the type broadly set forth hereinabove, but characterized by a simpler structure in comparison with existing devices of this type, the structure of this improved heel downholder being also advantageous in that it affords a relatively long stroke or movement before fully releasing the ski boot.

In this respect it may be noted that a safety ski binding, notably a heel downholder, can be referred to as a long release stroke device when the skier can raise the heel as far as onefourth inch or more, without causing the boot to be released. At the same time, this retaining force must be nearly constant. In fact, this resistance must not, under any circumstance, increase with the heel release stroke. A binding of this type is advantageous in that the boot cannot be released by brief shocks and on the other hand the retaining mechanism can be adjusted with a view to exert a relatively moderate retaining force permitting an automatic release of the ski boot in case of dangerous fall.

For these various reasons, the heel downholder according to this invention is characterized essentially in that the release lever and the cam-forming movable member controlling the heel-gripping jaw support are combined into a single and same member rigid with a third transverse pivot pin rotatably mounted in the base member, this third transverse pivot pin being formed in a manner already known per se with a pair of bearing edges urged by a compression spring through the medium ofa piston.

This heel downholder is advantageous in that its structure is particularly simple, since it comprises only three transverse pivot pins as contrasted with the structures of hitherto known heel downholders.

Besides, this heel downholder is extremely rugged and compact, and is also advantageous in that it affords a release stroke .of considerable length before actually releasing the boot heel.

A typical form of embodiment of the heel downholder according to this invention will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a side elevational view showing a heel downholder construction according to this invention;

FIG. 2 is a plane view from above of the same device;

FIG. 3 is a longitudinal axial section of the same device shown in its normal or skiing position;

FIG. 4 is a view similar to FIG. 1 but showing the device during the upward movement of the heel, before the latter is released;

FIG. 5 is a view similar to FIG. 4 but showing the device in its fully release position, the ski boot heel being released from the binding, and

FIGS. 6 and 7 are cross sections taken along the lines VI-Vl of FIG. I and VII-VII of FIG. 5, respectively.

In the drawings, the reference numeral 1 designates a ski, 2 is the heel bearing plate and 3 the ski boot to be releasably retained on the ski.

To this end, the heel downholder according to this invention comprises a jaw 4 adapted to grip the heel while bearing there against in the direction of the arrow V.

The reference numeral 5 designates the base member of the heel downholder, which is secured to the ski.

Furthermore, 6a denotes a cam-forming movable member adapted to control the retaining action exerted by the support 7 of said heel-gripping jaw 4. Besides, 6b is a release lever whereby the skier can control at will the heel release action when he wishes to free his boots of the skis.

To sum up, the heel downholder according to this invention comprises only three transverse pivot pins, namely a first transverse pivot pin 8 having pivotally mounted thereon the heel-gripping jaw support 7, a cam-following pin 9 mounted on said support and responsive to the cam-forming movable contl'ol member 6a, and eventually a third transverse pivot pin 10 rotatably mounted in said base member 5.

As clearly visible in FIG. 3, the base member-5 constitutes a housing enclosing a coil compression spring 11 extending horizontally therein.

The compression or force of this spring 11 is adjustable by means of a screw plug I2 adapted at the same time to seal the ingress to the spring-receiving cavity of the base member. This spring 11 is adapted to act upon the above-mentioned third transverse pivot pin by means ofa piston 13.

This third transverse pivot pin 10 has a flat face I4 formed thereon which constitutes a seat for the operative end of piston 13. As a consequence of the provision of this flat face, the pivot pin 10 comprises two edges coincident with two generatrices thereof which are disposed on either side of its center. Thus, in case of rotational movement of this pivot pin 10, the piston 13 will engage one of these edges 15, so as to create a resilient return torque urging the rotary pin 10 to its normal position in which the flat face 14 engages the registering end face of piston I3.

As also clearly apparent from the drawings, the cam-forming movable member 6a is an integral part of the release lever 6b.

At its front end the cam-forming member 60 comprises at its lower portion a notch 16 engaged by the cam-following pin 9 carried by the pivoting support 7 in the normal position of this support. However, this member 6a further comprises at its front end a cam face 17 overlying said notch I6 and adapted to be engaged by the cam-following pin 9 of support 7 when the heel-gripping jaw 4 is raised.

As will be explained presently, the member 6 constituting both the cam-forming element and the release lever of the device is rigid with the rotary pivot pin I0. Under these conditions the resilient retaining mechanism enclosed in the base member or housing 5 will control the support 7 through the medium of this dual-purpose member 6, and more particularly of the front portion 6a thereof, since the cam-following pin 9 of support 7 is normally retained in said notch 16.

As can be seen in the drawings the first transverse pivot pin 8 on which the support 7 is pivotally mounted is located at the rear end of base member 5 and substantially level with the upper portion of jaw 4.

Due to this particular arrangement this pivot pin 8 is relatively remote from the jaw 4, since the distance therebetween is a (FIG. 3). Under these conditions, when the skiers heel 3 is raised, the jaw 4 will pivot only slightly to the rear (see FIG. 4), so that this jaw remains in gripping engagement with the heel during a relatively long upward movement of the heel while continuing to urge it downwards.

The jaw 4 can be kept in its operative condition during a still longer upward movement of the heel end of the boot by inclining this jaw forwards and downwards by an angle a to the horizontal when it is in its normal position (FIG. 3).

As shown in FIG. 2, the jaw 4, when seen in plane view from above, comprises a curved surface 18 registering with the rear end of the heel. Thus, this end can rotate within the space bounded by this surface, when the boot is pivoted sidewise, as a consequence of the release of the toe end of the boot by the front safety abutment or like device of the ski binding system, in case of dangerous torsional movement of the skiers leg.

It will be noted that the jaw 4 exerts on the heel 3 only a vertical retaining force V, but no horizontal thrust H.

Thus, the heel downholder according to this invention cannot interfere with the proper operation of the front abutment device engaged by the toe end of the ski boot for holding this end against undesired side movements.

In the advantageous form of embodiment illustrated in the drawings the base member or housing 5 has the shape of a parallelepipedic block. The ends of the cam-following pin 9 carried by the pivoting support 7 project from the lateral walls of this base member and are advantageously provided with rollers 19.

The dual purpose member 6 constituting the cam-forming movable member and the release lever 6b actually consists of two identical lever-shaped flat members engaging the lateral faces of said base member 5.

These two levers are rigid with the ends of the third transverse rotary pivot pin I0 projecting slightly from the lateral walls of said base member. Moreover, these two levers are interconnected at their rear ends by a transverse member 20 extending slightly above the rear end of the heel downholder in the normal position of the device.

The assembly consisting of these two levers and their transverse connecting member 20 is made preferably in the form of a single sheet metal pressed member.

The transverse connecting member 20 of this assembly comprises a notch or cutout 21 adapted to be engaged by the point 22 of a ski stick. Thus, by depressing this member 20 by means of his stick the skier can bring the heel downholder to the position shown in FIG. 5 so as to free the heel when the user wishes to take his skis off. In fact, this action will cause the member 6 to rotate bodily in the clockwise direction as shown by the arrow F, in FIG. ll, and to carry along the camfollowing pin upwards through the medium of the nose portion 37 underlying the notch I6.

The support 7 of the heel gripping jaw is thus caused to pivot upwards about the pivot pin 8 in the clockwise direction F (FIG. 4), so that the pin 9 will eventually free itself from said notch 16 and slide along the cam face 17. However, this pin is finally retained by a nose portion 24 formed at the upper end of cam face 17. A suitable hairpin spring 23 is interposed between the base member 5 and the jaw support 7 for urging the jaw 4 to this position.

In the example illustrated the support 7 consists of a metal sheet pressing of substantially channel configuration when seen in plane view from above. However, the two wings of this member have substantially the shape of an L when seen in side elevation, the longer arm 26 thereof extending in a substantially horizontal plane in the normal position of the heel downholder, with the shorter arm 25 lying at the same time substantially vertically and ahead thereof. The two wings of this member engage the two sidewalls of base member 5.

The longer arm of the two wings of this member has its rear end pivotally mounted to the transverse pivot pin 8. Besides, the cam-following pin 9 of the heel downholder of this invention is located at the lower end of the arm 25 of the two wings of the same member.

This support further comprises a lower lug 27 extending in a substantially horizontal direction in the normal position of the device, this lug being adapted to constitute somewhat a heel downholder resetting pedal, i.e. for controlling the closing thereof by simply depressing or kicking down this lug by means of the heel portion 3 of the skiers boot. However, the support 7 further comprises an upper lug 28 registering with the lug 27.

The heel-gripping jaw 4 is disposed between these two lugs 27, 28 and engages a screw 29 rotatably mounted in these lugs. As this jaw cannot rotate about itself its vertical position can be adjusted by rotating the screw 29 in one or the other direction.

As will be seen in FIG. I, the upper edges 30 of the lateral wings of the release lever are level with the corresponding edges 31 of the longer arm 26 of support 7.

Besides, the U-shaped metal pressing constituting this support is advantageously closed at its upper end by a cover 32.

The heel downholder thus constructed has a compact and closed structure in its normal position (see FIGS. I and 2) which prevents the ingress of snow and also the formation of ice between the movable members.

The base member 5 as well as the heel plate 2 are advantageously secured to a plate 33 slidably mounted on the top surface of the ski, so that it can move in the axial direction thereof. This plate may be guided for example by a pair of guide members 38 secured to the top surface of the ski.

The base member 5 is advantageously secured to the plate 33 by means of vertical lugs 34 carried by said plate and engaging corresponding recesses 35 fonned in the lateral walls of the base member, and locking rivets 36 are also provided to this end.

The operation of the above-described heel downholder will be clearly understood from the drawings and notably from FIGS. 3 and 5 thereof.

As already explained hereinabove, the resilient retaining mechanism housed in the base member controls the pivoting support 7 by means of the pair of levers 6, more particularly the front portion 6a thereof.

Now the pressure exerted by the spring loaded piston 13 constantly urges the rotary pivot pin to the position illustrated in FIG. 3. Since this pin 10 is rigid with the levers 6, these will hold the support 7 and therefore the jaw 4 in their normal or skiing position as illustrated in FIGS. 1 and 3.

However, the heel portion of the boot is then resiliently retained, due to the particular arrangement of the mechanism enclosed in the base member 5 and also to the operative connection provided between this member 5 and the support 7. In fact, the pivot pin 10 of this support 7 can rotate about its axis when the torque exerted thereon exceeds the resilient return force exerted by the spring through said piston. This torque is obviously transmitted thereto via the pair of levers 6 when the pivoting support 7 tends to move upwards when the heel of ski boot is raised.

As long as the amplitude of this movement remains within reasonable limits and the effort exerted on the boot is of limited magnitude, the support 7 can move upwards without causing the ends of the cam-following pin 9 carried thereby to escape from the notches 16 formed on said control levers 6. Thus, these levers 6 are maintained in operative engagement with the pivoting support 7.

In the example illustrated the arrangement is such that the heel 3 can be raised to a maximum height h whereat the sup port 7 remains in engagement with the pair of control levers 6 (see FIG. 4).

It should be observed that in this position the boot heel itself is retained by the jaw 4. The resilient retaining mechanism of the heel downholder can still subsequently return the support 7 to its initial position, after this upward movement, this return movement being transmitted via the control levers 6, so that the heel is moved towards the ski.

Thus, this device permits the slight upwards movements of the heel portion of a ski boot, such as the movements normally required when skiing normally, for example when clearing a bump or when coming to a sudden stop, and also in case of forward fall without any severe consequence.

However, if a relatively important effort is exerted on the ski, the heel will continue its upward movement against the resistance of the resilient retaining mechanism. Under these conditions, the ends of the cam-following pin 9 carried by the support 7 escape from the retaining notches 16 when the upward movement of the heel has overstepped the endmost position illustrated in FIG. 4. The ends of this pivot pin will subsequently slide along the cam face 17 of the pair of control levers 6 until they engage, or abut against, the retaining noses 24.

But in any case the heel of the ski boot is freed from the jaw 4 before the support 7 reaches the above-described position.

However, it may be emphasized that the heel is not freed in a sudden manner, as contrasted with the mode of operation of hitherto known heel downholders of the same general type. In fact, the resilient heel retaining force remains substantially constant throughout the release stroke or movement, and decreases slightly before the complete release. This feature is also one of the essential advantages of the device constituting the subject matter of this invention, since it affords a relatively long release stroke before fully releasing the boot. Under these conditions, it is not necessary for the user to adjust the mechanism to a very hard position with a view to prevent an untimely or premature release of the boot. Thus, the user can select a relatively soft" adjustment for the retaining mechanism, so that he can safely rely on a positive release of the boot in case of severe fall.

However, another important feature characterizing this heel downholder resides in its extreme constructional simplicity,

notably the reduced number of pivot and hinge pins, since the device comprises only three transverse pivot pins, as contrasted with hitherto known heeldownholders which comprise an impressive number of such pins. Moreover, the number of component elements of this device is also extremely reduced.

Besides, the heel downholder according to this invention is constructionally very rugged and wear resistant. Furthermore, it is advantageous in that its overall dimensions are relatively small, since the assembly has the general configuration of a parallelepipedic block.

lclaim:

l. A downholder assembly for holding a ski boot heel portion on a ski, which comprises a base member adapted to be fixed with respect to the top surface of the ski, a pivoting member mounted on said base member about a first transverse pivot pin, ajaw on said pivoting member, said jaw being adapted to grip said heel portion and having an upper portion, a cam-following pin on said pivoting member, a third transverse pivot pin rotatably mounted on said base member, a pivoting lever rigid with said third transverse pivot pin and having a front portion, a cam member on said pivoting lever for controlling the movement of said cam-following pin from a first to a second position with respect to said cam member, said downholder being at a lowermost position when said camfollowing pin is at its first position, said pivoting lever being adapted to constitute a release lever for controlling the retraction of said cam member, said third rotary transverse pivot pin having a planar abutment surface including a pair of edges parallel to each other and to the axis of said third pivot pin, a piston having a complementary planar surface which is adapted to contact said abutment surface, the plane containing the abutment surface being perpendicular to the axis of the piston when the downholder is in its lowermost position, and a compression spring urging said piston against said edges.

2. The downholder as claimed in claim 1, characterized in that said first transverse pivot pin is located at the rear end of said base member and is substantially level with the upper portion of said jaw.

3. The downholder as claimed in claim 1, characterized in that said cam member is a notch and a cam face on said pivoting lever, said cam face being positioned above said notch, said cam-following pin being positioned in said notch at said first position when the downholder is at said lowermost position, said cam face receiving said cam-following pin at said second position when the pivoting member is moved upwardly.

4. The downholder as claimed in claim 3, characterized in that said notch is formed in the front portion of said pivoting lever and said notch is of a depth such that said cam-following pin will remain engaged in said notch during a certain portion of the upward movement of said pivoting member.

5. The downholder as claimed in claim 1, characterized in that said base member has substantially the shape of a parallelepipedic block and the ends of the transverse pivot pin on the pivoting member project from the lateral walls of said base member, and said pivoting lever is a pair of interconnected levers which extend along said lateral walls.

6. The downholder as claimed in claim 5, characterized in that the pivoting member has a substantially U-shaped configuration when seen in plane view from above, and each wing thereof is substantially L-shaped in configuration and has a major and a minor arm, the major arm is disposed substantially horizontally at the upper portion of the assembly and the minor arm extends forward and downward in the normal or skiing position of the downholder.

7. The downholder as claimed in claim 6, characterized in that the upper edges of the major arms of the two wings of said ing edges of the pair of levers constituting the pivoting lever. 

1. A downholder assembly for holding a ski boot heel portion on a ski, which comprises a base member adapted to be fixed with respect to the top surface of the ski, a pivoting member mounted on said base member about a first transverse pivot pin, a jaw on said pivoting member, said jaw being adapted to grip said heel portion and having an upper portion, a cam-following pin on said pivoting member, a third transverse pivot pin rotatably mounted on said base member, a pivoting lever rigid with said third transverse pivot pin and having a front portion, a cam member on said pivoting lever for controlling the movement of said camfollowing pin from a first to a second position with respect to said cam member, said downholder being at a lowermost position when said cam-following pin is at its first position, said pivoting lever being adapted to constitute a release lever for controlling the retraction of said cam member, said third rotary transverse pivot pin having a planar abutment surface including a pair of edges parallel to each other and to the axis of said third pivot pin, a piston having a complementary plaNar surface which is adapted to contact said abutment surface, the plane containing the abutment surface being perpendicular to the axis of the piston when the downholder is in its lowermost position, and a compression spring urging said piston against said edges.
 2. The downholder as claimed in claim 1, characterized in that said first transverse pivot pin is located at the rear end of said base member and is substantially level with the upper portion of said jaw.
 3. The downholder as claimed in claim 1, characterized in that said cam member is a notch and a cam face on said pivoting lever, said cam face being positioned above said notch, said cam-following pin being positioned in said notch at said first position when the downholder is at said lowermost position, said cam face receiving said cam-following pin at said second position when the pivoting member is moved upwardly.
 4. The downholder as claimed in claim 3, characterized in that said notch is formed in the front portion of said pivoting lever and said notch is of a depth such that said cam-following pin will remain engaged in said notch during a certain portion of the upward movement of said pivoting member.
 5. The downholder as claimed in claim 1, characterized in that said base member has substantially the shape of a parallelepipedic block and the ends of the transverse pivot pin on the pivoting member project from the lateral walls of said base member, and said pivoting lever is a pair of interconnected levers which extend along said lateral walls.
 6. The downholder as claimed in claim 5, characterized in that the pivoting member has a substantially U-shaped configuration when seen in plane view from above, and each wing thereof is substantially L-shaped in configuration and has a major and a minor arm, the major arm is disposed substantially horizontally at the upper portion of the assembly and the minor arm extends forward and downward in the normal or skiing position of the downholder.
 7. The downholder as claimed in claim 6, characterized in that the upper edges of the major arms of the two wings of said pivoting member are substantially level with the corresponding edges of the pair of levers constituting the pivoting lever. 